I have seen some threads saying how terrible they are. Is this just because they are not linked and can rotate in the bore? Or is there issues with them failing?

 

the lifter often gets blame for failing when its improper component matching elsewhere in the valvetrain that often causes it. the lifter has a pretty hard job to do, so to blame everything on "bad lifters" isn't telling the whole story.

that being said, lots of guys that have failures seem to have run them in applications with high spring pressures and aggressive lobe profiles with high lifts....things they were not designed to handle. couple that with improper push rod size and you've got several factors all working together to collapse the lifter. they seem to work for a lot of people when the valvetrain is set up properly but I wouldn't use them on anything more than a very mild setup.

 

I guess I should consider running a link bar. My set up isn't exactly mild and I will be running Brian Tooley .660 springs. I see morel has a good reputation but also heard they are tough to get a hold of.

 

I have them in my 408ci. 650 lift springs. 62# lift cam. No problems.

 

Sometime you can run into a inconsistency in the bleed down rate with one or more of the lifters in your set, it's kind of hit-and-miss.
I'd look at the BTR SLR lifters

 

The biggest "issue" with the LS7s is that most people are stupid and pretend they are some massive upgrade when they are simply another OEM lifter. The failure rate on them seems to be a little higher than older stuff but that could certainly be due to aggressive lobes and poor setup. Really though it is not like they are junk or anything, just a cheap OEM replacement.

 

For a cam and heads upgrade they are fine for an all out full engine build I would get something better. I have them with .650 springs and a big cam and have no problems. Also I think people use the wrong pushrods length with these lifters because it changes a bit.

 

They're definitely not an upgrade over stock, just a stock replacement; nothing more.

 

This looks like a cost effective upgrade compared to some of these $500 link bar set ups. Is anyone running the BTR SLR's?

 

I'm using LS7 lifters, in my 383, with .619 lift cam, and rev limiter set to 7200, no issues at all, and misc info, my power drops off at 6500 only see 7200rpm at the end of a quarter mile pass in fourth gear, have 4.08 gears

 

how did stock original lifters work?

 

I don't think anyone is saying the LS7 lifters are terrible. Many people run them without problems. The issue is the entire valvetrain.

When you run heavy valves, high spring rates, and fast ramp cams, you put a lot of stress on an OEM spec component. Can it survive? Sure. If you're setup is well optimized and setup correctly, the lifters will probably be ok. But merely ok.

And optimized means: milder endurance lobes, less spring pressure, and lighter valves combined with light and strong rockers and very strong pushrods.

What do I see most of the time? XE-R or LSK lobes, big stainless, heavy valves, and huge spring pressure to control those lobes with heavy valves. Then I see 5/16th pushrods and heavy aftermarket roller rockers. And after 10k miles the lifter fails or turns in the bore and takes out an engine. Sorry, I don't care if you are running them successfully or not. It's on borrowed time if you're not running a truly optimized setup that doesn't "loft" the lifter.

 

not sure if you are asking me, but I bought an engine that had low miles but sat up a while, so I figured new lifters wouldn't hurt, so don't know how stock lifters would have worked at 7200rpm

 

Does anyone know the difference in length in ls7 lifters and ones out of a 03 5.3?

 

They are essentially the same. The LS7s are a little longer, but the cup sits a little lower. It's a wash.

 

Lunati sells street linkbar lifters for 360. I was trying to decide between those or LS7 lifters with LS2 lifter trays. Still undecided.

 

https://ls1tech.com/forums/generatio...r-lifters.html

Brian's response on page 3.

My takeaways from it....the SLR's aren't anything much different from the LS7's except that they are valved for a slower leakdown rate. This helps you at lower rpm when the lifter will typically leak down too quickly since the oil pressure isn't sufficient to the point that it can prevent net lift losses. So noise levels and lower end power losses are reduced.

However it still doesn't help with higher rpm valve float....if your valvetrain is still out of control to the point that you're lofting the lifter, I'd imagine these would float valves worse than stock since they have tighter tolerances (oil can't escape as fast) and they have the same preload / travel range as the stock lifter. It's just as important to have the valvetrain under control with these as it is with stock lifters and as it is with ls7's as it is with morel's and lunati's etc etc.

There is no "magic lifter", you have to assess the entire valvetrain

 

people are blindly pushing LS7 lifters as an "upgrade" but never having even tried or had a problem with stock.

 

You mean stock LS1? I'm not running a cam with lifters with 144k miles on them. Too bad you can't get LS1 lifters anymore. Only LS7 from GM.

 

Well, my build is not even close to a moderate build with .660 springs .620 lift cam yadda yadda yadda. So now I need to select the right lifters....